The invention relates generally to a battery pulse charger using a solid-state device and method wherein the current going to the battery is not constant. The signal or current is momentarily switch-interrupted as it flows through either the first channel, the charge phase, or the second channel, the discharge phase. This two-phase cycle alternates the signal in the two channels thereby allowing a potential charge in a capacitor to disconnect from its power source an instant before the capacitor discharges its stored potential energy into a battery for receiving the capacitor""s stored energy. The capacitor then disconnects from the battery and re-connects to the power source upon completion of the discharge phase, thereby completing charge-discharge cycle. The battery pulse charger can also drive devices, such as a motor and a heating element, with pulses.
Present day battery chargers use a constant charge current in their operation with no momentary disconnection of the signal or current as it flows either: 1) from a primary energy source to the charger; or 2) from the charger itself into a battery for receiving the charge. Some chargers are regulated to a constant current by any of several methods, while others are constant and are not regulated. There are no battery chargers currently in the art or available wherein there is a momentary signal or current disconnection between the primary energy source and the charger capacitors an instant before the capacitors discharge the stored potential energy into a battery receiving the pulse charge. Nor are there any chargers in the art that disconnect the charger from the battery receiving the charge when the charger capacitors receive energy from the primary source. The momentary current interruption allows the battery a short xe2x80x9crest periodxe2x80x9d and requires less energy from the primary energy source while putting more energy into the battery receiving the charge while requiring a shorter period of time.
One aspect of the invention relates to a solid-state device and method for creating a pulse current to pulse charge a battery or a bank of batteries in which a new and unique method is used to increase and preserve for a longer period of time the energy stored in the battery as compared to constant-current battery chargers. The device uses a timed pulse to create a waveform in a DC pulse to be discharged into the battery receiving the charge.
One embodiment of the Invention uses a means for dual switching such as a pulse width modulator (PWM), for example, a logic chip SG3524N PWM, and a means for optical coupling to a bank of high-energy capacitors to store a timed initial pulse charge. This is the charge phase, or phase I. The charged capacitor bank then discharges the stored high energy into the battery receiving the charge in timed pulses. Just prior to discharging the stored energy into the battery, the capacitor bank is momentarily disconnected from the power source, thus completing the charge phase, and thereby leaving the capacitor bank as a free-floating potential charge disconnected from the primary energy source to then be discharged into the battery. The transfer of energy from the capacitor bank to the battery completes the discharge phase, or phase II. The two-phase cycle now repeats itself.
This embodiment of the battery pulse charger works by transferring energy from a source, such as an AC source, to an unfiltered DC source of high voltage to be stored in a capacitor or a capacitor bank. A switching regulator is set to a timed pulse, for example, a one second pulse that is 180 degrees out of phase for each set of switching functions. The first function is to build the charge in the capacitor bank from the primary energy source; the second function is to disconnect the power source from the capacitor bank; the third function is to discharge the stored high voltage to the battery with a high voltage spike in a timed pulse, for example, a one second pulse; and the fourth function is to re-connect the capacitor bank to the primary energy source. The device operates through a two-channel on/off switching mechanism or a gauging/re-gauging function wherein the charger is disconnected from its primary energy source an instant before the pulse charger discharges the high-energy pulse into the battery to be charged. As the primary charging switch closes, the secondary discharging switch opens, and visa-versa in timed pulses to complete the two phase cycle.
The means for a power supply is varied with several options available as the primary energy source. For example, primary input energy may come from an AC source connected into the proper voltage (transformer); from an AC generator; from a primary input battery; from solar cells; from a DC-to-DC inverter; or from any other adaptable source of energy. If a transformer means is the source of primary input energy, it can be a standard rectifying transformer used in power supply applications or any other transformer means applicable to the desired function. For example, it can be a 120-volt to 45-volt AC step-down transformer, and the rectifier can be a full-wave bridge of 200 volts at 20 amps, which is unfiltered when connected to the output of the transformer. The positive output terminal of the bridge rectifier is connected to the drains of the parallel field-effect transistors, and the negative terminal is connected to the capacitor bank negative.
The Field Effect Transistor (FET) switches can be IRF260 FETs, or any other FET means to accomplish this function. All are in parallel to achieve the proper current of the pulses. Each FET may be connected through a 7-watt, 0.05-ohm resistor with a common bus connection at the source. All the FET gates may be connected through a 240-ohm resistor to a common bus. There also may be a 2 K-ohm resistor between the gates and the drain bus.
A transistor means, for example an MJE15024 transistor, as a driver for the gates, drives the bus and in turn, an optical coupler drives the driver transistor through the first channel. A first charging switch is used to charge the capacitor bank, which acts as a DC potential source to the battery. The capacitor bank is then disconnected from the power rectifier circuit. The pulse battery charger is then transferred to a second field effect switch through the second channel for the discharge phase. The discharge phase is driven by a transistor, the transistor driven by an optical coupler. With a second or discharge switch on, the capacitor bank potential charge is discharged into the battery to receive the charge. The battery receiving the charge is then disconnected from the pulse charger capacitor bank to repeat the cycle. The pulse charger may have any suitable source of input power including: 1) solar panels to raise the voltage to the capacitor bank; 2) a wind generator; 3) a DC-to-DC inverter; 4) an alternator; 5) an AC motor generator; 6) a static source such as a high voltage spark; and 7) other devices that can raise the potential of the capacitor bank.
In another embodiment of the invention, one can use the pulse charger to drive a device such as a motor or heating element with pulses of energy.